My guess is because before, the way Nintendo discussed clone characters made it seem as if they were trying to hide or ignore the fact that they were clones, which made people mis-perceive the characters' inclusions as laziness (in actuality, clones are almost consistently the last characters to be added to a roster). Outright admitting that they're clones with slight deviations makes it feel more acceptable because Nintendo's effectively taking the "clone character" stigma in stride without it coming off as obnoxious.

It's weird how just acknowledging that they're subcharacters and alternate playstyles makes them feel so much more acceptable.